Is this wobble through the handlebars when decelerating & when he has one or both hands off the handlebars? Both the front & rear wheels on motorcycles have a natural resonant flutter frequency, like a supermarket trolly wheel that flaps like crazy at certain speeds. Its easy to envisage the front wheel flutter rotating about the axis of the steering head, but also the rear wheel can do the same thing rotating around the steering head, but as the distance from the steering head to the rear wheel contact point is much greater the rear wheels flutter frequency is lower. The tricky part is when the natural flutter frequency of the front wheel becomes a harmonic of the rear wheels frequency. As the mass of the rear wheel & its lever ( basically all the motorcycle from the stem rearwards) has considerably more inertia the rear wheels attempt to flutter excites the front wheel into flutter mode. All bikes do this, but the road speed at which this occurs can be modified by design. The usual option is to design this flutter harmonic point to occur at low road speeds (30 to 45 mph for those that like feudal measures) and use the rider as an organic steering damper. Coast down through this speed range on any brand new, bog stock bike with both hands off the bars & you will spot the build & decay of harmonic steering flutter

As I said before all bikes have a point of harmonic flutter, so why is this a problem for your friend now & not before?

Things that will make the flutter point more obvious include tyres worn flat in the middle from too much slabbing, adding weight to the rear of the bike especially rigid hard panniers & double especially a loaded top box, rear suspension with too much sag, too low tyre pressures.

So start with the obvious. tell him to ride with both hands on the bars... death grip not necessary.
Cast a critical eye over how much crap he is carrying on the bike... or post a piccy so we can all waggle a finger at him.
Set tyre pressures @ 36psi front 42 psi rear from cold
Set preload so the bike sags 35 mm @ the rear with rider & all luggage installed. My guess a 12 year old VFR with stock shock & spring this will be impossible, but let us know how much sag their is now.
Check condition of tyres. Never ridden on Shinkos but any tyre worn flat in the centre from slabbing will cause problems long before its at legal limits.

Good luck & get back to us with how its going.

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Thank you for the response.

The wobble is there when he rides with both hands on the bars, it can be while he accelerates, holds a steady speed or starts to slow. Yes there is a lot of crap on the bike and that's what I figured was causing it initially. We removed all the gear though and it's still there.

We have already set the tire pressure to what you suggest as we'll as looking for flat spots on the tire. Sag is all the way up.....but there is still probably more like 42mm of sag.

Lose head bearing maybe? What about raising the foks 1-2mm to see if that changes anything? We will be in San Diego until Friday morning and hope to solve it by then.

The wobble is there when he rides with both hands on the bars, it can be while he accelerates, holds a steady speed or starts to slow. Yes there is a lot of crap on the bike and that's what I figured was causing it initially. We removed all the gear though and it's still there.

We have already set the tire pressure to what you suggest as we'll as looking for flat spots on the tire. Sag is all the way up.....but there is still probably more like 42mm of sag.

Lose head bearing maybe? What about raising the foks 1-2mm to see if that changes anything? We will be in San Diego until Friday morning and hope to solve it by then.

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When I encountered similar symptoms on my '94, it was a similar situation: I was loaded for a trip when I first noticed it, but could make it happen even after unloading. Adding pre-load (stock shock) helped, as did unloading the bike. What finally resolved the problem was replacing the steering head bearings.

After removing the bearings from the bike, I re-assembled them in my hands, and could feel the slight notch in each one. While they were on the bike however, I could feel nothing but smooth operation.

As above, start with the easy stuff first, but I believe that your primary suspect should be steering-head bearings. They're cheap and easy to replace, provided you have the right tools and something to support the bike with while you've got the front end off. I've still got the special socket for the nut, and the pin-spanner wrenches; if they're required on your 2000, you're welcome to the use of them. I'd offer work-space here in Morro Bay, but I don't even have a driveway anymore.

The wobble is there when he rides with both hands on the bars, it can be while he accelerates, holds a steady speed or starts to slow. Yes there is a lot of crap on the bike and that's what I figured was causing it initially. We removed all the gear though and it's still there.

We have already set the tire pressure to what you suggest as we'll as looking for flat spots on the tire. Sag is all the way up.....but there is still probably more like 42mm of sag.

Lose head bearing maybe? What about raising the foks 1-2mm to see if that changes anything? We will be in San Diego until Friday morning and hope to solve it by then.

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By flat spots on the rear tyre I mean the centre of the tyre worn down flattening the profile rather than flat spots as if the tyre had been locked & skidding. Should be easy to spot. I assume that the bike has the Shinko 009's fitted front front & rear at the same time. Mismatched tyres, especially at different points of their wear life can cause these kinds of problems all by themselves.

The normal wear pattern for tyres as they age, especially with lots of slab miles is for the rear tyre to flatten off in the middle of the tread & for the front to become more pointed. The rear wear is obvious, the bike is pushed along by the engine through the rear tyre contact patch. Do some miles heavily loaded & even constant, moderate cruising speeds can wear a tyre out surprisingly quickly. The front tyre wears to a point because it does not do much work until the brakes are applied, then the tyre contact patch is mashed into the road. It is designed to flatten out at the contact point to give more grip under brakes & this flattening out wears the outside edges of the contact point much more than the centre. If a bike, as rough rule of thumb, can go from 100mph to zero in half the time it can go from zero to 100 then you can get an idea of the forces involved.

So I would consider replacing both tyres as a set before stripping the bike down & changing steering head bearings, especially as its such a labour intensive job. On the upside actually checking the steering head bearings is dead simple & should be your first step. Lob the VFR up on its centre stand (leave the luggage on so the front wheel is off the ground) and check the bearings. Turn the bars left to right, by fingertip force only. The bars should turn with a little resistance, not flop from lock to lock (bearings too loose) & without a notchy feel, especially just off centre (bearings worn & damaged, replace). Next step kneel down and grasp the bottom of the forks from the front & pull back & forward firmly (any clunking? bearings too loose). To tighten the steering head bearings leave the bike on the centre-stand. Loosen the top triple clamp allen bolts & handlebar clamps bolts on the fork tube. Loosen & back off the chromed centre bolt on the top triple clamp & slide up the triple clamp up the steering stem. Lift clear the locking washer (with tabs) & using a drift loosen the castellated locking nut. Using the drift tighten in small steps the lower castellated nut, testing the tension as described above. Once you are satisfied with the bearing tension tighten down the locking nut (lining up the notches so you can refit the locking washer tabs in the notches) using the drift, but being cautious not to tighten the lower nut in the process. Slide down the triple clamp & tighten down the centre nut firmly, then finally tighten the allen bolts clamping the fork tubes followed by the handlebar clamps.

It is my opinion (from 15,000km away I admit) that as the bike clearly changed from being OK to being a wobbly mess during the trip that something has changed in a more marked way than the gradual change that comes with stuffed head bearings. Now that you have checked their tension what next?

You have eliminated the weight of the touring luggage so cross that off my list.

Replace the tyres as a set with stock-sized quality sport-touring rubber... Tyres have a dramatic effect on the riding experience & you are touring for the fun of it so don't cheap out here.

If the wobble is still present after re-tensioning the steering head bearings & replacing the rubber then the next cab off the rank is the rear suspension. If the sag with rider & luggage with max pre-load is 42mm then the rear spring is too soft. I'll assume that with the preload at max you have adjusted the rebound damping to max as well to help control the spring. It is possible that the shock has lost its damping through aged seals, even if oil leaks are not apparent the shock could have well lost its damping due to it suddenly loosing gas pressure.

I would'nt raise the forks up in the triple clamps as what you are doing there is experimenting on ways of disguising the symptoms of a problem, not a cure.

Has anyone found a source for a passenger backrest for 6th gen VFRs besides Corbin? I've checked with Sargent and it's not offered as an option, and Givi makes a topcase with backrest pad but I don't really want a topcase.

It spins fine and when the front is suspended it doesn't seem to have slop.

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There have been some great answers on your headshake problem. Google .headshake' and you'll find many different make and model bikes do this around 40-50mph, especially while decellerating.

I have a Honda ST1100 and the 50K+ miles I rode it, I have run 3 different front tires. The OEM tire had no headshake, Bridgestone BT023s have NO headshake, while Avon Storm and Storm ultras shake like a dog crapping a peach seed. I know of dozens of ST1100s that can not run Avon Storms on the front, doesn't maytter if the head bearings are stock or changed to tappered roller bearings.

You could have mechanical problems, but i'll bet a dollar to a doughnut that the bike doesn't like that front tire.

There have been some great answers on your headshake problem. Google .headshake' and you'll find many different make and model bikes do this around 40-50mph, especially while decellerating.

I have a Honda ST1100 and the 50K+ miles I rode it, I have run 3 different front tires. The OEM tire had no headshake, Bridgestone BT023s have NO headshake, while Avon Storm and Storm ultras shake like a dog crapping a peach seed. I know of dozens of ST1100s that can not run Avon Storms on the front, doesn't maytter if the head bearings are stock or changed to tappered roller bearings.

You could have mechanical problems, but i'll bet a dollar to a doughnut that the bike doesn't like that front tire.

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My experience with Avons on ST11's was that they needed a shitload of air pressure, like 48 PSI, to work.

Thanks fellas.
There is hardly a scratch on her. Where there are scratches, it has been masked by touch up paint.
All fluids are sparkly clean and fresh, and topped right up.
Poor thing is currently parked half in and half out of my carport and will be for a few weeks yet. Im getting a slab laid for a new shed in the coming weeks, but till then, its under a bike cover

Whats this bikes fasination for getting the front wheel off the ground??
Accelerate moderately in first gear, hit a little bump, and up it comes.
Same in second gear exiting a tight bend, and the handlebars do that little dance in your hands that say "we have lost contact with the road!"

I also joined the highway, and for the first time held it WOT in second and the front was off the ground by a few inches. I felt the steering get light for a second or two, then the light impact of the front wheel coming back to earth.

Whats this bikes fasination for getting the front wheel off the ground??
Accelerate moderately in first gear, hit a little bump, and up it comes.
Same in second gear exiting a tight bend, and the handlebars do that little dance in your hands that say "we have lost contact with the road!"

I also joined the highway, and for the first time held it WOT in second and the front was off the ground by a few inches. I felt the steering get light for a second or two, then the light impact of the front wheel coming back to earth.

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I think that's all due to that rear bag you have mounted on the thing. I have never powered wheelied mine in over 17K. I'm sure it could do it, but these are pretty piggish bikes on the scales...

I think that's all due to that rear bag you have mounted on the thing. I have never powered wheelied mine in over 17K. I'm sure it could do it, but these are pretty piggish bikes on the scales...

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There was only a 600ml coke, a jumper and two sandwiches in that bag.
I was speaking to a guy about it at work tonight and he would borrow his mates on occassion, and it would do the same thing. The slightest bump in the road in first and sometimes second would see the wheel come up.
Hell, Im all for it

Sad ending to a great little plane. First build in England in 64, first flown in 65.
It had its last flight in 81, where it was stripped of its engines (Sold to Rolls Royce) and transported to where it is now. Rumoured to have a Boeing 707 cockpit in it, but no one has been able to get permission to open it up and have a look from its owner.I know roughly where the guy is, but not 100% sure.